Anna's Hummingbird vs Olivaceous Thornbill
Calypte anna compared with Chalcostigma olivaceum
Side-by-Side Comparison
| Attribute | Anna's Hummingbird | Olivaceous Thornbill |
|---|---|---|
| Scientific Name | Calypte anna | Chalcostigma olivaceum |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Trochilidae | Trochilidae |
| Conservation Status | Least Concern | Least Concern |
| Length | 10.0 cm (3.9 in) | — |
| Wingspan | 12.0 cm (4.7 in) | 16.3 cm (6.4 in) |
| Weight | 4.3 g (0.15 oz) | 7.3999999999999995 g (0.26 oz) |
| Diet | Nectar, small insects, and tree sap. Visits a wide variety of native and ornamental flowering … | Nectarivore of high Bolivian and Peruvian páramo; short bill accesses small open flowers. Gleans insects … |
| Clutch Size | 2 | 2 |
| Population Trend | — | — |
Size Comparison
Habitat Comparison
Shared Habitats
None
Anna's Hummingbird only
Olivaceous Thornbill only
Anna's Hummingbird
Chaparral, coastal sage scrub, gardens, parks, and open woodland along the Pacific coast. One of few hummingbirds not fully migratory.
Song & Call Comparison
Anna's Hummingbird
Male produces a complex, scratchy song with buzzy 'dzzzzt' notes. Gives a nasal 'chee-chee-chee'. Males sing year-round, even in winter; one of few hummingbirds with true song.
Olivaceous Thornbill
Buzzy, high-frequency trill with insect-like quality; sustained continuous vibration with rapid amplitude modulation.
Geographic Range & Migration
Anna's Hummingbird
Western North America from southern British Columbia along the Pacific coast to Baja California. Range has expanded northward.
Olivaceous Thornbill
Widespread in high Andean puna grassland from Peru to Bolivia and northwestern Argentina. 3,200–4,800 m.
Conservation Status
Anna's Hummingbird
Olivaceous Thornbill
How to Tell Them Apart
Anna's Hummingbird
Metallic bronze-green upperparts. Males have an iridescent rose-red crown and gorget. Females have green upperparts with grey underparts and a small red gorget patch.
Medium-length, straight, thin black bill
Olivaceous Thornbill
About These Birds
Anna's Hummingbird
Anna's hummingbird is the most common hummingbird along the Pacific coast and one of only three species resident in the United States year-round. Males perform spectacular dive displays, plummeting from 40 meters and pulling up with a loud chirp produced by tail feathers. Their body temperature can drop to near ambient at night to conserve energy.
Olivaceous Thornbill
A small hummingbird (11-12 cm) found in Andean puna and páramo from Peru to Bolivia at 3,500-4,800 m. Olive-green plumage with subtle throat iridescence. Nectarivore of high-altitude flowering plants. One of the drabbest thornbills. Tolerates extreme cold.